Radian Translation On Other Language:

radian\ra"di*an\ (-an), n. [from radius.] (math.) an arc of a circle which is equal to the radius, or the angle measured by such an arc. [radian n : the unit of plane angle adopted under the system international d'unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees) [syn: rad]

The radian is the standard unit of angular measure, used in many areas of mathematics. An angle's measurement in radians is numerically equal to the length of a corresponding arc of a unit circle, so one radian is just under 57.3 degrees (when the arc length is equal to the radius). The unit was formerly an SI supplementary unit, but this category was abolished in 1995 and the radian is now considered an SI derived unit. The SI unit of solid angle measurement is the steradian.

Noun1. the unit of plane angle adopted under the Systeme International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees) (synonym) rad (hypernym) angular unit (part-meronym) milliradian

A unit of plane angle measure equal to the angle subtended at the center of a circle by an arc equal in length to the radius of the circle. Note: One radian is equal to 360°/2, which is approximately 57° 17' 44.6".